1. Field
The present application relates generally to the operation of overlay networks, and more particularly, to methods and apparatus for discovery of peer-to-peer overlay networks.
2. Background
A network in which member nodes obtain services in the absence of server-based infrastructure is referred to herein as a “peer-to-peer” overlay network. In a peer-to-peer overlay, peer nodes co-operate with each other both to provide services and to maintain the network. Peer-to-peer overlay networks can be built on top of an underlying network, such as a network utilizing the Internet Protocol (IP).
For a node to participate in a peer-to-peer overlay network, it must discover the names of existing overlay networks and meta-data associated with these overlay networks. The meta-data typically includes the IP addresses of “introducer” nodes that can help the joining node join a particular overlay network.
There are several traditional approaches to solving the overlay network discovery problem. A node may find the names of available overlay networks using an out-of-band mechanism like a web search. Next, the node may use a domain name services (DNS) to resolve any discovered overlay network names to find the Internet Protocol (IP) addresses of introducer nodes. In a second approach, a well-known super overlay network is used. Any node that wishes to discover other overlay networks joins the super overlay network and queries nodes in the super overlay network for information about other overlay networks. Unfortunately, these techniques are inefficient and make it difficult for a node to discover and join a particular overlay network
Therefore, it is desirable to have a simple cost effective mechanism that operates to allow a node to discover peer-to-peer overlay networks.